[ntp:questions] Compensating for asymmetric delay on a per-peer/server basis?

Paul tik-tok at bodosom.net
Sat Sep 13 13:27:31 UTC 2014

On Sat, Sep 13, 2014 at 1:46 AM, Rich Wales <richw at richw.org> wrote:
> Any thoughts?

Something is wrong with your home machine but there's nothing you can
do with stock NTP to fix your offset.

As posted earlier I see exactly the same ~2ms offset.  However as
noted -- given that you're on the same network -- these two lines are

-    .PPS.            1 u   13   16  372    8.168   -2.126   4.585
-    2 u    2   16  333    9.689    2.146   3.930

and these two are pretty bad (and given the same polling interval
might also be junk)

+   .GPS.            1 u   45   64  377   35.222    6.542   2.864
+  .PPS.            1 u   18   64  377  191.192    4.890   8.968

My original question remains.  Do you have a production need to remove
the offset or is it for aesthetic reasons?

Regarding shaping.   An extremely cursory look suggests you can use a
Linux qdisc to insert a delay (shape to effective speed) in NTP
traffic so if you have an appropriate box to place between you modem
and your home network you could try that -- after you resolve your
current problem.

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